The wife of a Santa Ana man accused of sexually abusing his foster children is now behind bars facing charges of her own.

Maria Hernandez, who goes by Esther, was charged with being an accessory after the fact. She entered a not guilty plea Thursday and will return for a preliminary hearing on March 26.

The 59-year-old is accused of trying to hide evidence after her husband, 66-year-old Felipe Hernandez, allegedly raped their 16-year-old foster child, who they later adopted.

"She walked in on her husband having sex with one of the girls, who was under her care, who was a minor," said prosecutor Whitney Bokosky.

The suspected abuse began in their Santa Ana home when the girl was 11 years old. Prosecutors allege Esther threatened family members to lie to authorities.

"She also became very angry. She beat Jane Doe and then she sent her off to live with another family member," said Bokosky.

The charges against Esther are not true, another adopted daughter told Eyewitness News. The daughter, who is now 18 years old, is also an alleged victim and did not want to be identified.

"She's like not the type of person that would be an accomplice to something like what they're accusing her of. For her, her daughters are always first," she said.

The 18-year-old was reluctant to talk about her 66-year-old father. Police allege he's seen abusing her on a video.

"I was never raped," she told us during our interview.

I asked her if anything inappropriate happened.

"Inappropriate in that your dad is not supposed to do that to you, like touching," she replied.

She alleges he molested her for several months last year. Police started investigating last month after a third adopted sister, now 15 years old, told a school counselor that Felipe Hernandez raped her when she was 9.

He was arrested last month and has pleaded not guilty. His bail was set at $1 million, and his wife's was set at $20,000.

Authorities say there may be other potential victims. The Hernandez's may have had up to 40 foster kids in their care over the years.

Orange County Children and Family Services has a 24-hour hotline to report child abuse: Child Abuse Registry Hotline at (800) 207-4464.